TAILORx the trilogy.

Top Line: Bored of headlining on this side of the pond, TAILORx is now seeing its name in lights at ESMO.

The Study: We must start with a slow clap for Sparano, et al for possibly getting the most traction out of a single study in oncologic history. This now onc-famous cohort of >9700 women prospectively followed after Oncotype DX testing was pretty inclusive as long as the cancer was hormone-receptor(+) / HER2(-) and pT1c-2 any grade or pT1b if grade >1. Just as a reminder, all those with low-risk scores (≤10) received endocrine monotherapy, and those with intermediate-risk scores (11-25) were randomized to endocrine therapy +/- the addition of chemo. This iteration tells the tale of the 14% of women labeled “high-risk” with a score ≥26 (n=1389) who all received endocrine therapy + chemo, typically with a taxane, anthracycline or both. Since this is a single-arm study, it’s important to first make a note of historical controls. Take B20, for instance, that randomized a clinically-similar cohort of women to tamoxifen +/- chemo, where the rate of freedom from distant recurrence without chemo was 66% at 10 years. (This same cohort, by the way, was used to validate Oncotype DX in the first place, producing a significant interaction test between risk score and benefit from chemo—thus the single-arm chemo here.) So what was freedom from distant recurrence among “high-risk” women receiving chemoendocrine therapy on TAILORx? 93%. Granted, this is only at 5 years, but needless to say it’s not a track to hit 66% in another 5.

TBL: Compared to historical controls, women with high-risk Oncotype DX scores ≥26 derive a huge advantage in disease control with the addition of chemo, supporting strategies to brand this test as predictive. | Sparano, JAMA Oncol 2019